How the 2021 Detroit Tigers defied the odds

Have the Detroit Tigers Been Lucky?

Luck always plays a huge role in baseball, and it can be hard to quantify, but we have a few weapons at our disposal. We can look at Detroit’s run differential, their expected weighted on-base average (xwOBA) vs. their actual weighted on-base average (wOBA), their performance in close games, and how they fared in “clutch” situations.

• The Tigers had a -59 run differential, which suggests a 75-87 record
• Tigers hitters had an xwOBA of .306 and an actual wOBA of .306
• Tigers pitchers allowed an xwOBA of .332 and an actual wOBA of .324
• The Tigers went 23-23 in one-run games, and 12-8 in extra-inning games
• Tigers hitters ranked 14th in clutch performance
• Tigers pitchers ranked 1st in clutch performance

The run differential is within reason, and their performance in close games isn’t a red flag (the Mariners, for instance, had a -51 run differential, but went 33-19 in one-run games, and 14-7 in extra innings).

But that clutch performance really stands out. You can read the definition of Clutch here, but it essentially compares performance in high-leverage situations — those times when the game hangs in the balance — to context-neutral situations.

Detroit Tigers pitchers really stepped up their game at the most important times this season. Casey Mize, for instance, was significantly better with men on base (3.90 FIP) than with the bases empty (5.31 FIP). That helped him to the 7th best Clutch rating among pitchers with 100 innings this year. Wily Peralta finished 4th in Clutch rating among pitchers with 80 innings.

Unfortunately, clutch performance is not considered a repeatable skill, so Mize, Peralta, and the Tigers could just as easily be on the negative side of the ledger next year.

It seems a fair amount of the extra wins in 2021 were the result of luck. But of course there’s that old saying about luck…